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Surgical resection of early stage hepatocellular carcinoma is standard clinical practice; however, most tumours recur despite surgery, and no perioperative intervention has shown a survival benefit. Neoadjuvant immunotherapy has induced pathological responses in multiple tumour types and might decrease the risk of postoperative recurrence in hepatocellular carcinoma. We aimed to evaluate the clinical activity of neoadjuvant cemiplimab (an anti-PD-1) in patients with resectable hepatocellular carcinoma.

Osteopontin is an adhesive glycoprotein implicated in numerous diseases associated with inflammation and remodeling. There are several structural domains in osteopontin that are of particular interest. The RGD motif is a cell attachment sequence shown to be critical for cell adhesion through αv-containing integrins. In close proximity to the RGD domain is the thrombin cleavage site. Previous observations suggest that thrombin cleavage of osteopontin occurs in vivoand may be physiologically important. To study the functional significance of osteopontin cleavage by thrombin, we made glutathione S-transferase-osteopontin fusion proteins. These proteins contain either the N- or C-terminal domains expected to be formed following thrombin cleavage at the Arg169-Ser170 peptide bond. We compared these osteopontin fragments with native osteopontin in their ability to support adhesion of several different cell lines and identified the receptors mediating these interactions. Our data show that the N-terminal osteopontin fragment, which contains the RGD domain, supports adhesion of a melanoma cell line that is unable to bind native osteopontin. This suggests that osteopontin adhesive interactions may be regulated by thrombin cleavage. We also demonstrate that osteopontin contains a cryptic binding activity, which can be recognized by a novel osteopontin receptor. This receptor has been identified as the α9β1integrin.

The highly organized structure of the Drosophila ovary makes it an ideal system for studying mechanisms of differential gene expression. Here we report the identification of a 171 bp sequence from the 5′ end of the hsp26 gene that functions as a female germ-line-specific transcriptional regulator when linked in two copies to a basal promoter. The regulator is active only in nondividing cells of the germ line, i.e., only in nurse cells and oocytes. It is not active in any examined tissue or cell type outside of the female germ line. Copper nuclease footprinting studies show that the germ line regulator contains two binding sites for each of two different ovarian nuclear factors. Point mutations in the DNA target sites of either nuclear factor abolish in vitro binding and in vivo transcriptional activity, indicating that each factor is a positive activator of nurse cell/oocyte transcription. The two factors may represent different classes of activator proteins, since an increase in the copy number of one factor’s DNA target site cannot compensate for a decrease in the copy number of the other factor’s target site.

The specification of cell fates along the dorsoventral axis of the Drosophila embryo is dependent on the asymmetric distribution of proteins within the egg and within the egg’s outer membranes. Such asymmetries arise during oogenesis and are dependent on multiple cell-cell interactions between the developing oocyte and its neighboring somatic follicle cells. The earliest known such interaction involves the generation of a signal in the oocyte and its reception in the follicle cells lying on the dorsal surface of the oocyte at ∼ stage 10 of oogenesis. Several independent lines of investigation indicate that the fs(1)K10 (K10) gene negatively regulates the synthesis of the signal in the oocyte nucleus. Here we present data that indicate that the accumulation of K10 protein in the oocyte nucleus is a multistep process involving: (1) the synthesis of K10 RNA in nurse cells, (2) the rapid transport of K10 RNA from nurse cells into the oocyte, (3) the localization of K10 RNA to the anterior margin of the oocyte, and (4) K10 protein synthesis and localization. K10 RNA is transported into the oocyte continuously beginning at ∼ stage 2. This indicates a high degree of selectivity in transport, since most RNAs synthesized in stage 2 and older nurse cells are stored there until stage 11, when nurse cells donate their entire cytoplasm to the oocyte. The sequences responsible for the early (pre-stage 11) and selective transport of K10 RNA into the oocyte map to the 3′ transcribed non-translated region of the gene. None of the other identified genes involved in dorsoventral axis formation are required for K10 RNA transport. Two such other genes, cappuccino (capu) and spire (spir) are, however, required for the subsequent localization of K10 RNA to the oocyte’s anterior end.